Laundry treatment appliance

ABSTRACT

A laundry treatment appliance has a laundry treatment apparatus with a rotatably mounted laundry drum held in a housing such that it can move. The laundry treatment apparatus has an electric motor for driving the laundry drum, a control system for actuating the electric motor, a vibration sensor for detecting a vibratory movement of the laundry treatment apparatus, and a vibration-damping apparatus for damping a vibratory movement. The vibration-damping apparatus has at least one controllable vibration damper which can be actuated in dependence on the vibratory movement of the laundry treatment apparatus for changing the vibration-damping properties of the vibration damper. The control system, in the event of a malfunction in a power supply system, actuates the electric motor such that the electric motor generates electrical energy from a rotary movement of the laundry drum and makes it available to the control system.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority, under 35 U.S.C. §119, of German application DE 10 2010 027 158.6, filed Jul. 14, 2010; the prior application is herewith incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a laundry treatment appliance, in particular a laundry treatment appliance having an active vibration-damping system.

A laundry treatment appliance, for example a washing machine, a tumble dryer or a washer dryer, typically has a washing tub (also called a wash tub), a laundry drum which is rotatably mounted in the washing tub, and an electric motor for driving the laundry drum. The washing tub is held in the housing of the laundry treatment appliance such that it moves, for example by a plurality of vibration dampers.

In a spin-drying cycle of the laundry treatment appliance, a load which bears against the circumference of the laundry drum and is non-uniformly distributed can cause undesirable movements of the washing tub which, when the washing tub is rigidly coupled to the outer wall of the laundry treatment appliance, can lead to movement of the laundry treatment appliance, and at least to undesirable development of noise. The same is also true in a washing cycle due to a free-falling and rolling load in the laundry drum.

Various measures for determining an unbalance of this kind are known in order to be able to react to an unbalance in spin-drying or washing cycles. The method described in German patent DE 102 34 053 C1 (corresponding to U.S. Pat. No. 6,973,392) is based on a measurement of the periodic fluctuation in the electrical power consumption by the drive motor of the laundry drum. German patent DE 44 31 846 C2 proposes comparing the torques of the electric motor which are to be applied in the event of acceleration of the laundry drum with the torques which are to be applied in order to maintain a constant rotation speed. Furthermore, German patent DE 103 45 591 B1 (corresponding to U.S. patent publication No. 2005/0066450), German patent DE 10 2004 053 216 B3 (corresponding to U.S. patent publication No. 2006/0010936) and German patent DE 10 2005 037 144 B4 (corresponding to U.S. Pat. No. 7,921,494) disclose various types of vibration sensors for detecting vibratory movements of an internal unit, which is suspended such that it can vibrate, of a laundry treatment appliance about a center of mass in at least one spatial axis.

German patent DE 10 2005 037 144 B4 also describes a laundry treatment appliance in which the internal unit is suspended such that it can vibrate by at least one spring, which is mounted between the housing and preferably the upper region of the washing tub, and at least one frictional damper, which is mounted between the washing tub and the lower region of a side wall or the base of the housing. The springs and frictional dampers, together with the mass of the washing tub and the contents of the washing tub, form the vibration and damping system of the laundry treatment appliance.

Frictional dampers contain, in their simplest form, an outer body (for example tube) and a tappet, preferably composed of plastic, which can move in the outer body or coaxially to the outer body. A rubber-like, porous pad which can be saturated with grease or a grease-like liquid is, for example, inserted between the tappet and the outer body. The task of this pad is to increase the friction between the tappet and the outer body and to convert the kinetic energy, for example of a washing tub, into frictional heat.

The damping behaviour of a frictional damper of this kind is largely constant. It changes only on account of the pad and the frictional surfaces heating up, this leading to wearing of the pad over the course of time. This so-called “settling” can lead to a reduction in the frictional forces over the service life of the laundry treatment appliance, as a result of which the damping effect of the frictional dampers is reduced. The washing tub can also execute so-called yawing movements which cannot be effectively suppressed by such frictional dampers given an unfavourable arrangement.

In order to avoid the above-described rigid damping behaviour, frictional dampers have been developed which have frictional surfaces of different configuration which lead to a variable vibration damping, with the damping property changing as the stroke of the tappet increases. The degree of damping is typically virtually zero in the case of a small stroke and increases as the deflection of the tappet increases.

This type of frictional damper is also called a “free-stroke frictional damper”. The properties of these frictional dampers can be influenced by selecting the contours of the frictional surfaces and are substantially constant over the service life of the laundry treatment appliance, apart from natural aging processes. A free-stroke frictional damper of this kind is described, for example, in published, non-prosecuted German patent application DE 40 14 166 A1.

European patent EP 0 878 574 B1 (corresponding to U.S. Pat. No. 5,907,880) discloses a method for actively damping vibrations in a laundry treatment appliance. The frictional dampers contain a magnetorheological medium in this case, it being possible to change the rheological properties (for example viscosity) of the medium by applying a magnetic field in order to thus influence the damping properties of the frictional damper. In the method proposed in this document, a deviation in the rotation speed of the electric motor is detected and an actuating signal is generated if the deviation in rotation speed exceeds a threshold value for this deviation in rotation speed. This actuating signal generates a magnetic field in the interior of the frictional damper, the flux density of the magnetic field being proportional to the actuating signal and therefore to the magnitude of the deviation in rotation speed.

However, controllable frictional dampers of this kind have not been used as standard in laundry treatment appliances to date since their functionality is lost or greatly restricted in the event of a power cut because the magnetorheological liquid is typically of low viscosity if not excited and accordingly cannot have any or have only poor damping properties. Particularly in the case of large unbalances, the continued rotation of the laundry drum in the event of a power cut can further lead to very severe deflections of the washing tub, and this can lead to damage to the laundry treatment appliance and cause disturbing noise.

SUMMARY OF THE INVENTION

It is accordingly an object of the invention to provide a laundry treatment appliance which overcome the above-mentioned disadvantages of the prior art methods and devices of this general type, which has an actively controllable vibration-damping system, and which laundry treatment appliance also ensures the laundry drum reliably slows to a stop in the event of a malfunction in the power supply system.

The laundry treatment appliance contains a laundry treatment apparatus having a rotatably mounted laundry drum, with the laundry treatment apparatus being held in a housing of the laundry treatment appliance such that it can move. The laundry treatment appliance further has an electric motor for driving the laundry drum in rotation, a control system for actuating the electric motor with it being possible to connect the control system to a power supply system, at least one vibration sensor for detecting a vibratory movement of the laundry treatment apparatus, and at least one vibration-damping apparatus for damping a vibratory movement of the laundry treatment apparatus. In this case, the vibration-damping apparatus has at least one controllable vibration damper which can be actuated by the control system in dependence on the vibratory movement of the laundry treatment apparatus, which is detected by the at least one vibration sensor, for the purpose of changing the vibration-damping properties of the vibration damper. In addition, the control system is formed in such a way that, in the event of a malfunction in the power supply system which is associated with the control system, the control system actuates the electric motor in such a way that the electric motor obtains electrical energy from a rotary movement of the laundry drum and makes this available to the control system, and actuates the at least one vibration damper in dependence on the vibratory movement of the laundry treatment apparatus, which is detected by the vibration sensor, in order to damp a vibratory movement of the laundry treatment apparatus, and/or actuates the electric motor in order to brake the rotary movement of the laundry drum.

The laundry treatment appliance of the invention contains an actively controllable vibration-damping system. The actively controllable vibration-damping system is operational only when the (motor) control system and the vibration-damping system are supplied with electrical energy. In order to prevent unbalances in the laundry treatment apparatus damaging the laundry treatment appliance in the event of a malfunction in the power supply system (for example a power cut), the vibration-damping system is also kept operational in the event of a malfunction in the power supply system of this kind.

To this end, the (motor) control system is formed in such a way that, in the event of a malfunction in the power supply system which is associated with the (motor) control system, the (motor) control system actuates the electric motor in such a way that the electric motor obtains electrical energy from a rotary movement of the laundry drum and makes this available to the control system. Electric motors can act like a current generator and induce a voltage in the stator winding on account of the continued rotation of the laundry drum in the event of a power cut, the voltage being made available to the control system via the motor connection lines. Electrical energy can be supplied to the intermediate circuit of the motor control system given suitable actuation of the power electronics. Therefore, the motor control system can also maintain its functionality in the event of a power cut, as long as kinetic energy is made available by the laundry drum slowing to a stop.

Since the main control system of the laundry treatment appliance stops functioning, typically after a few moments, due to a lack of energy supply in the event of a power cut, the motor control system no longer has a communication partner. Therefore, the motor control system has to be able to make independent decisions about the continued implementation of suitable safety measures in the event of a malfunction in the power supply system. The (motor) control system is therefore configured in such a way that, in the event of a malfunction in the power supply system, the (motor) control system actuates the at least one vibration damper as a function of the vibratory movement of the laundry treatment apparatus, which is detected by the vibration sensor, in order to damp a vibratory movement of the laundry treatment apparatus, and/or actuates the electric motor in order to brake the rotary movement of the laundry drum.

In this case, the electrical energy which is induced in the electric motor is preferably temporarily stored in an energy-storage device in the electric motor or the motor control system.

The “laundry treatment apparatus”, sometimes also called the internal unit in the prior art disclosed in the introductory part, contains, in particular, the rotatably mounted laundry drum for accommodating the laundry to be washed and/or dried and also usually the washing tub or wash tub for accommodating the laundry drum.

The “vibration sensor” used may be a sensor for directly detecting a vibration or a device for determining a vibratory movement from other measurement variables, such as rotation speed, torque or power consumption by the electric motor. In one embodiment, the vibration sensor is a sensor which detects the movement of the laundry treatment apparatus or the washing tub of said laundry treatment apparatus.

The “vibration-damping apparatus” has at least one (actively) controllable vibration damper. That is to say, the vibration-damping apparatus can have one, two, three, four or more controllable vibration dampers and, in addition, further vibration dampers with invariable damping properties.

The motor control system is configured according to the invention in such a way that, in the event of a malfunction in the power supply system which is associated with the motor control system, the motor control system actuates the electric motor in such a way that the electric motor obtains electrical energy from a rotary movement of the laundry drum and makes this available to the control system, and actuates the at least one vibration damper in dependence on the vibratory movement of the laundry treatment apparatus, which is detected by the vibration sensor, in order to damp a vibratory movement of the laundry treatment apparatus, and/or actuates the electric motor in order to brake the rotary movement of the laundry drum. This means that the electrical energy obtained by the electric motor is sufficient to further operate the motor control system and to further detect and evaluate the measurement values using the vibration sensor in the event of a malfunction in the power supply system.

In one refinement of the invention, at least one rotation-speed and/or torque sensor for detecting a rotation speed, a fluctuation in rotation speed, a torque and/or a fluctuation in torque of the electric motor is also provided. The control system is then additionally formed in such a way that it also actuates the electric motor and/or the at least one vibration damper as a function of the measurement variable which is detected by the at least one rotation-speed and/or torque sensor in the event of a malfunction in the power supply system which is associated with the control system.

In a further refinement of the invention, at least one device for detecting a phase position of an unbalance of the laundry drum is also provided. The control system is then additionally formed in such a way that it also actuates the electric motor and/or the at least one vibration damper in dependence on the detected phase position of the unbalance, that is to say in a phase-dependent manner relative to the position of the unbalance, in the event of a malfunction in the power supply system which is associated with the control system. In this case, the damping properties of the at least one controllable vibration damper are preferably regulated in advance of the position of the unbalance of the laundry treatment apparatus.

Since the respective vibratory movement is known from the at least one vibration sensor, the respective rotation speed, fluctuation in rotation speed, torque and/or fluctuation in torque of the electric motor are known from the rotation-speed and/or torque sensor and the respective phase position of the unbalance of the laundry drum is known, the motor control system can also take the optimum safety measures in the event of a malfunction in the power supply system in order to prevent damage to the laundry treatment appliance.

In a still further refinement of the invention, the laundry treatment appliance also has a door-locking apparatus. The control system is then preferably formed in such a way that it actuates the door-locking apparatus in dependence on the measurement variable which is detected by the rotation-speed and/or torque sensor, in the event of a malfunction in the power supply system which is associated with the control system. In this way, the door-locking system can be prevented from being released, even in the event of a power cut, as long as the laundry drum is still rotating or still rotating too fast.

Furthermore, the control system is preferably configured in order to identify a malfunction in the power supply system which is associated with the control system. In this advantageous embodiment, the control system can immediately react to a malfunction in the power supply system and initiate the required safety measures. A malfunction in the power supply system can preferably be achieved by monitoring the input voltage and frequency. Similarly, by virtue of this functionality of the motor control system, the motor control system itself can identify when the malfunction in the power supply system is rectified again. In this case, the motor control system can then optionally automatically return to normal actuation of the electric motor.

The at least one controllable vibration damper of the vibration-damping apparatus is preferably an electrically controllable frictional damper. The frictional damper is preferably a frictional damper with a magnetorheological or electroviscous medium (in particular liquid). However, frictional dampers in which the frictional forces of two touching frictional surfaces which are opposite one another can be varied by electromechanically changing the contact pressure can also be used. Similarly, frictional dampers in which a passage opening between two adjacent chambers which are filled with a fluid (for example air or liquid) can be narrowed or widened in order to change the damping properties can be used. Instead of the passage opening with a variable opening cross section, it is also feasible to use a switchable capillary pore membrane or the like.

A method for operating a laundry treatment appliance, in particular the above-described laundry treatment appliance of the invention, is characterized in that the control system, in the event of a malfunction in the power supply system which is associated with the control system, actuates the electric motor in such a way that the electric motor obtains electrical energy from a rotary movement of the laundry drum and makes this available to the control system, and actuates at least one vibration damper in dependence on a vibratory movement of the laundry treatment apparatus in order to damp the vibratory movement of the laundry treatment apparatus, and/or actuates the electric motor in order to brake the rotary movement of the laundry drum.

The above embodiments regarding the advantages of the laundry treatment appliance according to the invention correspondingly apply to this operating method.

In one refinement of the invention, the control system also actuates the electric motor and/or the at least one vibration damper in dependence on a rotation speed, a fluctuation in rotation speed, a torque and/or a fluctuation in torque of the electric motor in the event of a malfunction in the power supply system which is associated with the control system.

In a further refinement of the invention, the control system also actuates the electric motor and/or the at least one vibration damper in dependence on a phase position of the unbalance of the laundry drum in the event of a malfunction in the power supply system which is associated with the control system.

In a yet further refinement of the invention, the motor control system also actuates a door-locking apparatus of the laundry treatment appliance, specifically preferably in dependence on a rotation speed or a torque of the electric motor, in the event of a malfunction in the power supply system which is associated with the control system.

According to the invention, one or more of the following safety measures can be taken in a laundry treatment appliance having an actively controllable vibration-damping system in the case of a malfunction in the power supply system.

In the case of small, non-critical unbalance values, the kinetic energy of the laundry drum can be used to supply energy to the motor control system for as long as possible. In this case, only a minimum quantity of energy is drawn from the system and the laundry drum has a long slow-down time. Secondly, the quantity of energy drawn can also be maximized and excess energy can be converted into heat in the windings of the electric motor, so that rapid braking and accordingly a short slow-down time of the laundry drum result following a power cut.

In the case of small, non-critical unbalance values, only a little energy or no energy at all is required for the controlled vibration dampers. The system can run largely undamped.

In the case of relatively large to critical unbalance values, the energy which is returned to the motor control system is required to supply energy to the controlled vibration dampers. In this case, the slow-down time of the laundry drum depends on the quantity of energy which is required to supply energy first to the motor control system and sensors and second to the controlled vibration dampers. This can ensure that the laundry drum slows to a stop as far as possible in a vibration- and impact-free manner.

Provided that the quantity of energy required for the motor control system and the controllable vibration damper does not correspond to the maximum quantity of energy which can be drawn, the differential quantity of energy can, as already described above, be converted into heat in the stator windings of the electric motor. In this case, the slow-down time of the laundry drum after a power cut is reduced further.

No more electrical energy can be obtained when the drum reaches a standstill. It is not necessary to supply power to the controllable vibration dampers in this case either. The further run time of the motor control system now depends only on the remaining capacity of the intermediate circuit capacitors and can be reduced by active discharging.

Provided that the power cut ends again before the drum reaches a standstill, the motor control system independently makes a decision about the further rotation-speed profile of the electric motor. If the current rotation speed is still above a spreading rotation speed, that is to say the rotation speed at which the entire load is pressed against the edge of the laundry drum by centrifugal forces, the rotation speed could be returned to the original rotation speed, but at least the current rotation speed is maintained.

The present invention can be used for any desired laundry treatment appliances, for example washing machines, tumble dryers and washer dryers.

Other features which are considered as characteristic for the invention are set forth in the appended claims.

Although the invention is illustrated and described herein as embodied in a laundry treatment appliance, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.

The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a highly simplified block diagram of a laundry treatment appliance according to one preferred exemplary embodiment of the invention; and

FIG. 2 is a highly simplified block diagram of the laundry treatment appliance according to a further preferred exemplary embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the figures of the drawing in detail and first, particularly, to FIG. 1 thereof, there is shown a laundry treatment appliance 5 (for example a washing machine). The laundry treatment appliance 5 has a washing tub 10 and a laundry drum 12, which is rotatably mounted in the washing tub 10, for accommodating the laundry (load) to be treated. The washing tub 10 and the laundry drum 12 together form a laundry treatment apparatus of the invention. The laundry drum 12 is preferably equipped with an apparatus for passive unbalance compensation (for example a ball-type balancing device).

The rotation axis of the laundry drum 12 runs, for example, substantially horizontally (front-loader) or vertically (top-loader). The laundry drum 12 is driven by an electric motor 14, the drive axle of the electric motor either directly or indirectly providing driving, for example, by a V-belt.

The electric motor 14 is driven by a (motor) control system 18 which is connected to a power supply system or a power supply network 19 for the purpose of supplying energy. In addition, the washing machine 5 also has a main control system 20 which is connected to the motor control system 18 and likewise to the power supply network 19. As an alternative to this, the (motor) control system 18 can, as illustrated in FIG. 2, be connected to the power supply network 19 by the main control system 20.

The laundry treatment apparatus 10-12 is held in the housing of the washing machine 5 such that it can vibrate. To this end, at least one spring 22 is provided, the spring preferably being mounted in the upper region between the washing tub 10 and the housing. A vibration-damping apparatus is also provided, the vibration-damping apparatus having at least one vibration damper 24 which is preferably mounted in the lower region between the washing tub 10 and the housing of the washing machine 5.

According to the invention, the vibration dampers 24 are controllable vibration dampers, it being possible for the damping properties of the vibration dampers to be actively actuated by the motor control system 18. Whereas these vibration dampers 24 can also be optionally actuated by the main control system 20 during normal operation of the washing machine 5, it has to be possible to actuate the vibration dampers using the motor control system 18 in the event of a power cut (that is to say a malfunction in the power supply system 19).

Frictional dampers with a magnetorheological or electroviscous medium are preferably used for these controllable vibration dampers 24. The main control system 20 and the motor control system 18 can influence a magnetic field or a control voltage of these frictional dampers 24, this causing a change in the at least one rheological or electroviscous property of the medium and therefore the damping properties of the vibration dampers 24.

Various measures are provided for monitoring the laundry treatment apparatus 10-12. The electric motor 14 (or selectively the motor control system 18 too) is equipped with a rotation-speed and/or torque sensor 26. The rotation-speed and/or torque sensor 26 detects a rotation speed, a fluctuation in rotation speed, a torque, a fluctuation in torque or the like of the electric motor 14. The power consumption by the electric motor 14 can be optionally detected too.

At least one vibration sensor 28 is also provided in order to detect a vibratory movement of the laundry treatment apparatus 10-12 in at least one spatial direction. In principle, any desired sensors and devices which are known or will become known to a person skilled in the art and which measure at least one of the physical units travel/distance, speed or acceleration can be used for this purpose. An acceleration sensor can preferably be used as the vibration sensor 28.

The measurement results from the rotation-speed and/or torque sensor 26 and from the vibration sensor 28 are made available to the motor control system 18 which then actuates firstly the electric motor 14 and secondly the at least one controllable vibration damper 24 in accordance with these measurement results and possibly other conditions (for example current washing program etc.). Furthermore, the motor control system 18 can also actuate a door-locking apparatus 32, so that the washing machine door can be opened only when the laundry drum 12 is no longer rotating or no longer rotating too quickly.

During normal operation, that is to say with a functioning power supply system, the main control system 20 and the motor control system 18 are supplied with electrical energy by the power supply network 19 directly (FIG. 1) or in series (FIG. 2), and the electric motor 14, the vibration dampers 24 and the sensors 26, 28 are supplied with electrical energy by the power supply network 19 via the motor control system 18. In the event of a malfunction in the power supply system 19 (for example power cut), the main control system 20 stops operating after a few moments and the electric motor 14 is no longer supplied with power either. In other words, there is no longer any flow 30 of energy to the electric motor 14.

The motor control system 18 is formed in such a way that it identifies a power cut of this kind, for example on the basis of the input voltage and frequency of the power supply network, and accordingly can initiate suitable safety measures. Firstly, the motor control system 18 actuates the electric motor 14 such that the electric motor functions as a generator and the kinetic rotation energy of the slowing-down laundry drum is converted into electrical energy in order to make this electrical energy available to the motor control system 18, the controllable vibration dampers 24, the sensors 26, 28 and the door-locking apparatus 32 (flow 30 of energy in the direction of the motor control system 18). In this case, the electrical energy induced in the electric motor 14 is preferably temporarily stored in an energy-storage device of the electric motor 14 or the motor control system 18.

In this way, “emergency operation” of the motor control system 18 is also ensured in the event of a power cut. The motor control system 18 can therefore ensure, in the case of a slowing-down laundry drum 12, that the laundry drum does not cause any damage to the washing machine even when there is an unbalance. In particular, the motor control system 18 can also actuate the controllable vibration dampers 24 for damping a vibratory movement of the laundry treatment apparatus 10-12 and/or brake the electric motor 14. The motor control system 18 can preferably derive actuating variables for at least one vibration damper 24 and the electric motor 14 from the measurement variables of a fluctuation in rotation speed and/or power, a phase position of an unbalance and a movement of the washing tub. 

1. A laundry treatment appliance, comprising: a housing; a laundry treatment apparatus having a rotatably mounted laundry drum, said laundry treatment apparatus held in said housing such that said laundry treatment apparatus can move; an electric motor for driving said rotatably mounted laundry drum in rotation; a control system for actuating said electric motor, it being possible to connect said control system to a power supply system; at least one vibration sensor for detecting a vibratory movement of said laundry treatment apparatus; at least one vibration-damping apparatus for damping the vibratory movement of said laundry treatment apparatus, said vibration-damping apparatus having at least one controllable vibration damper which can be actuated by said control system in dependence on the vibratory movement of said laundry treatment apparatus, the vibratory movement being detected by said at least one vibration sensor, for changing vibration-damping properties of said vibration damper; said control system formed such that, in an event of a malfunction in the power supply system associated with the said control system, said control system: actuates said electric motor such that said electric motor obtains electrical energy from a rotary movement of said rotatably mounted laundry drum and makes the electrical energy available to said control system; and actuates said at least one vibration damper in dependence on the vibratory movement of said laundry treatment apparatus, which is detected by said vibration sensor, in order to damp the vibratory movement of said laundry treatment apparatus; and/or actuates said electric motor to brake the rotary movement of said rotatably mounted laundry drum.
 2. The laundry treatment appliance according to claim 1, further comprising at least one further sensor detecting at least one of a rotation speed, a fluctuation in the rotation speed, a torque or a fluctuation in the torque of said electric motor; and wherein said control system actuates at least one of said electric motor or said at least one vibration damper in dependence on a measurement variable which is detected by said at least one further sensor in an event of a malfunction in the power supply system associated with the said control system.
 3. The laundry treatment appliance according to claim 1, further comprising at least one device for detecting a phase position of an unbalance of said rotatably mounted laundry drum; and wherein said control system actuates at least one of said electric motor or said at least one vibration damper in dependence on a detected phase position of the unbalance in an event of a malfunction in the power supply system associated with said control system.
 4. The laundry treatment appliance according to claim 2, wherein: said laundry treatment appliance has a door-locking apparatus; and said control system actuates said door-locking apparatus in dependence on the measurement variable detected by said at least one further sensor in an event of the malfunction in the power supply system associated with said control system.
 5. The laundry treatment appliance according to claim 1, wherein said control system is configured in order to identify a malfunction in the power supply system associated with said control system.
 6. The laundry treatment appliance according to claim 1, wherein said at least one vibration damper of said vibration-damping apparatus is an electrically controllable frictional damper.
 7. A method for operating a laundry treatment appliance having a laundry treatment apparatus with a rotatably mounted laundry drum, the laundry treatment apparatus being held in a housing of the laundry treatment appliance such that the laundry treatment apparatus can move, the laundry treatment appliance further having an electric motor for driving the rotatably mounted laundry drum in rotation, a control system for actuating the electric motor and the control system being connectable to a power supply system, and at least one vibration-damping apparatus for damping a vibratory movement of the laundry treatment apparatus, which comprises the steps of: in an event of a malfunction in the power supply system associated with the power supply system, performing, via the control system, the steps of: actuating the electric motor such that the electric motor obtains electrical energy from a rotary movement of the rotatably mounted laundry drum and makes the electrical energy available to the control system; and actuating at least one vibration damper in dependence on the vibratory movement of the laundry treatment apparatus to damp the vibratory movement of the laundry treatment apparatus; and/or actuating the electric motor to brake the rotary movement of the rotatably mounted laundry drum.
 8. The method according to claim 7, which further comprises actuating, via the control system, at least one of the electric motor or the at least one vibration damper in dependence on at least one of a rotation speed, a fluctuation in rotation speed, a torque or a fluctuation in torque of the electric motor in an event of a malfunction in the power supply system associated with the control system.
 9. The method according to claim 7, which further comprises actuating, via the control system, at least one of the electric motor or the at least one vibration damper in dependence on a phase position of an unbalance of the rotatably mounted laundry drum in an event of a malfunction in the power supply system associated with the control system.
 10. The method according to claim 7, which further comprises actuating, via the control system, a door-locking apparatus of the laundry treatment appliance in dependence on one of a rotation speed or a torque of the electric motor in an event of a malfunction in the power supply system associated with the control system. 